Indicator for controllable propellers



M. W. MANGHESTER INDICATOR FOR CONTROLLABLE PROPELLERS Feb. 7, 1939. 2,146,401

5 sum-sheet 1 Filed Oct. 29, 1934 Feb. 7, 1939.

M. w MANCHESTER v 2,146,401

INDICATOR FOR CONTROLLABLE PROPELLERS Filed Oct. 29, 1934" s Sheets-Sheet 2 Patented Feb. 7, 1939 UNITED STATES INDICATOR FOR CONTROLLABLE PROPELLERS Mitchell W. Manchester, Williamsport, Pa., assignor, by mesne assignments, to Aviation Mannfacturing Corporation, Chicago, Ill., a corporation of Delaware Application October 29, 1934, Serial No. 750,407

21 Claims.

- justable means for automatically limiting the pitch changes within predetermined limits.

A further object of the invention is to provide a pitch-indicator adapted to be operated by reversible gearing driven by the engine which drives the propeller and means for conjointly controlling the direction of reversible pitch change gearing and the direction of the indicator.

A further object of the invention is to provide means for synchronizing the pitch indicator with the pitch-limiting means for the propeller blades.

Other objects of the invention will appear from the description.

This invention consists in the several novel features hereinafter set forth and more particularly defined by claims at the conclusion hereof.

In the drawings:

Fig. 1 is a diagrammatic perspective of the pitch indicator, the device for operating the reversible pitch change gearing, the pitch indicator, and the device for conjointly controlling said gearing and the driving mechanism for said indicator. Fig. 2 is a vertical longitudinal section of the manually operable control device for simultaneously engaging the engine driven driving mechanism for the indicator and for engaging the gearing for changing the pitch of the propeller blades. Fig. 2ais a section taken on line 2a 2a' of Fig. 2. Fig; 3 is a horizontal section through the pitchindicator. Fig. 4 is a front elevation of the pitchindicator. Fig. 5 is a vertical section on l ne 5-5 of Fig. 4, through the pitch-indicator. Fig. 6 is a section on line 6-6 of Fig. 5. Fig. '7 is a sect on on line 'I'--! of Fig. 3. Fig. 8 is a detail of the cam slide for coupling and uncoupling the pitch-indicator from the engine driven shaft for operating the indicator. 9-9- of Fig. 8. Fig. 10 is a detail of the slip connection between the pointer of the indicator and the shaft which shifts the ponter. Fig. 11 is a vertical section of a modification of the control i, device forsimultaneously coupling and uncou- Fig. 9 is a section taken on line pling the pitch-change gearing and the gearing for operating the pitch-indicator. Fig. 12 is a vertical section of a pitch indicator mechanism adapted to be controlled by the device shown in Fig. 11. Fig. 13 is asection taken on line l3-l3 of Fig. 14, of a modified form of the invention in which the pointer of the pitch indicator is mounted to move rectilinearly.

Fig. 14 is a side elevation-of the indicator shown in Fig. 13. Fig. 15 is a section taken on line l5-I 5 of Fig. 13.

The invention is exemplified in connection with a longitudinally shiftable collar 64 provided with right and left worms 6! and ,68, for engaging and driving in either direction high-ratio speed-reduction gearing for controlling the pitch of the propeller blades, illustrated in patent to Smith I No. 1,886,602, to which reference may be had for an exemplification of a controllable pitch propeller and gearing for increasing'and decreasing the pitch of the propeller blades, which is engaged by said collar to cause the gearing to be operated while the propeller isrevolving. A handle 2| is provided for shifting the collar 64 to the pitchchange gearing to increase or decrease the pitch of the propeller blades, as more fully set forth in said patent.

The collar 64, as set forth in Patent No. 1,886,602, is held against rotation and is movable from a neutral position into position to bring either of its worms 68, 6'! into engagement with the reduction gearing for increasing and decreasing the pitch of the blades, which is mounted in the propeller hub, by a rotatable sleeve 65, which is provided with helical slots into which studs 65' on collar 64 extend, so that rotation of the sleeve will shift the collar axially.

The control handle 2| is slidably mounted in a sleeve 43 (Fig. 2) which is fixedly secured by a nut 44 on a panel 45 and within convenient reach of the pilot. The handle 2| is fixed to a stem 46 which is axially slidable in sleeve 43. To the inner end of stem 46 one end of a sheathed flexible cable 4'! is fixed and this is connected to the rotatable sleeve 65, so that when the flexible cable 41 is shifted byiinward movement of the handle ,7 2!, the sleeve 65 will be rotated in one direction and when the handle 2| is pulled outwardly, it will rotate the sleeve 65 in the reverse direction to control the axial movements of the gear collar 64 from its neutral position to positions to engage either of the worms 68, 61 with the pitch change gearing shown in Patent No. 1,886,602.

The pitch-indicator (Figs. 1-5) comprises a suitable casing 22, a dial 23 having suitable calibrations thereon for pitch indications and mounted in a chamber in the front of casing 22, and a pointer 24 fixed to a shaft 25 to swing in front of the dial.

A flexible shaft 28 for operating the indicator is driven by a gear l9 which is adapted to mesh with the usual tachometer drive of the engine, so it will be driven at a speed corresponding to the speed of the engine. Shaft 28 terminates at and drives a shaft-section 28 which is journaled in a plate 21 which is secured to a bracket 28 which is rigid or integral with the casing 22 of the indicator. A pinion 29 is secured to the inner end of shaft-section 28 and is driven constantly while the engine is operating.

The pointer 24 is operated through speed reduclng gearing by a pinion 3| which is fixed to a vertical shaft 38 which is journaled in the casing 22, so that the movement of the pointer 24 over the scale on the dial 23 will correspond to the pitch changes of the propeller blades. The reduction-gearing between shaft 38, to which pinion 3| is fixed, and the pointer-shaft 25 comprises (Fig. 3) a worm or screw 33 on shaft 3|; a worm gear 34 meshing with worm 33 and mounted to rotate on the pointer-shaft 25 which is journaled in the casing 22; a pinion 35 integral with worm gear 34; a gear 38 which is mounted on a shaft 31 journaled in bearings in the gear casing 22 and meshes with pinion 35; a pinion 38 integral or rigid with gear 38; and a gear 39 which meshes with pinion 38 and is secured to the pointer-shaft Reversible gearing is provided between the engine-driven pinion 29 and the gear 3| for driving the speed reducing gearing for the pitch indicator in opposite directions according to the change eifected in the pitch of the propeller blades responsively to the movements of the gear collar 84. This reversible gearing comprises a gear 48 which is journaled in a pair of plates 4| which are pivoted on the hub of pinion 29 and a gear 42 which is also journaled in said hangers or plates. Gear 48 is in constant mesh with pinion 29 and gear 42 is in constant mesh with gear 48. By shifting the plates 4| around the axis of pinion 29, gears 48, 42 may be brought into neutral position so that both gears 48 and 42 will be disengaged from pinion 38 which operates the pitch indicator when the pitch change gearing is idle, or shifted to bring gear 48 into mesh with pinion 38 to drive the indicator gearing in one direction, or shifted to bring gear 42 into mesh with and simultaneously disengaging gear 48 from, pinion 3| to operate the indicator-gearing in the reverse direction. This exemplifies gear mechanism for engaging the indicator gearing to the indicator in either direction from the pinion 29 and the constantlyv driven engine driven shaft 28.

The handle 2| which controls the gear-collar 84 for the pitch change gearing is also connected to control the reversible gearing for operating the pitch indicator. A bracket (Fig. 2) is secured on the sleeve 43 in which the stem of the handle 2| is mounted and a lower sleeve 52 is fixed in said bracket. secures this bracket 5| and sleeves 43, 52'together. A plunger 54 is slidably mounted in lower sleeve 52 and is provided with a lug 55 which extends through a slot in sleeves 43-52 into an annular groove 58 in the stem 48 of handle 2|.

- A sheathed flexible cable 51 has one of its ends hired to the plunger 54 and its other end extends A bolt 53 rigidly and removably into the bracket 28 on the gear casing 22 of the pitch indicator, and is secured to a plunger 58. Said plunger is slidable in bracket 28 and is provided with a stem 59 which extends through a lug 88 on a cam slide 8| which is slidably mounted in bracket 28 under the stem. Said slide is provided with a cam slot comprising communicating-portions 18, II and 12. One of the pivotally movable plates 4| in which gears 48, 42 are mounted is provided with a stud 13 which extends into the cam slot so thatlongitudinal movement of the slide 8| will swing plates 4| and gears 48, 42. When stud 13 is confined in the portion H of the slot, both gears will be in neutral position, or disengaged from pinion 3|, and the gearing between pinion 3| and the pointer 24 will be idle. When the stud I3 is in the portion 12 of the cam slot, gear 48 will mesh with pinion 3| and drive the latter from pinion 29. When stud 13 is in portion 12 of the cam slot, gear 48 will mesh with, and gear 42 will be disengaged from pinion 3|, so the gearing between pinion 3| and the pointer will'be driven in one direction. When the stud I3 is in portion 18 of the cam slot, gear 48 will be disengaged from, and gear 42 will mesh with pinion 3|, so the latter ,will be driven through gears 48, 42 in the reverse direction. The longitudinal movement of the cable 51 and stem 59 is transmitted to the cam-slide 6| through a pair of springs 14 and I5 interposed between washers on the stem 59 and the opposite faces of lug 68 on said slide. By means of these springs, the slide is yieldingly shifted to prevent locking of the gears 48, 42 and pinion 3| as they are engaged.- The cam-slide 8| is mounted to slide in a guideway or slot 18 in the bracket 28. A cover plate 11 is secured to the top of bracket 28 to enclose plunger 58, stem'59 and cam-slide 8|. This exemplifies mechanism controlled by the handle which controls the pitch change gearing -for simultaneously controlling the operation of the pitch indicator in either direction from the constantly running shaft 28, which is driven from the engine in one direction only.

In the controllable propellersof the type in which the engaging gear is manually controlled as in the propeller of the aforesaid Smith patent, there is automatic means for limiting the pitch variation which acts at the end of predetermined high and low pitch changes and this mechanism is independent of the manually controlled gear-collar 84. To cause the pointer 24 of the pitch indicator to cease its movement when the pitch change ceases or at the end of the predetermined pitch limits, while the gear collar 84 remains engaged with the pitch change gearing, a slip-connection is provided between the pointer 24 and its shaft which permits the reduction gearing for the indicator to continue to run after the pitch changes cease. This slip-connection consists of a spring-washer 88 between a screw 8| which is threaded into the front end of shaft 25 and the front of the pointer. Adjustable stops, such as screws 82, are carried by the dial 23 to positively arrest the pointer, if the control handle 2| is not shifted to disengage collar 84 from the pitch change gearing and the indicator is not uncoupled from shaft 28 before the blades reach the predetermined pitch limits. Screws 82 are secured in arcuate slots 83 in the dial so that they may be set to stop the pointer to correspond with the pitch limits'provided for in the adjustable automatic pitch limit mechanism. These stops and slipconnections also rectify any slight variations ing the pitch indicator which is self-correcting when the blades reach the predetermined pitch limits. i A

The operation of the mechanism will beas follows: Normally, the handle 2| will be in a position to hold the gear collar 94 in its neutral position and the cam-slide Si in position to hold gears 40. and "disengaged from pinion 9|, while the propeller and shaft 20 are driven by the engine. When a pitch increase is to be effected the pilot will shift the handle 2! in one direction to cause the appropriate worm on collar 54 to engage and drive the pitch change gearing, and to simultaneously shift through flexible shaft 51 the cam-slide 6| to bring one of the gears Ill, 92 into engagement with the pinion 3|, so that the reduction gearing of the pitch indicator will be driven to shift the pointer 24. As the pitch of the blades is increased, the pointer 24 'will swing to correspondingly indicate the pitch increase on the dial. If the blades 'reach'the high pitch limit, while the collar 6t remains engaged, the pointer 24 will strike one of the stops at and be arrested to retain the proper pitch indication while the indicator gearing and a portion of the pitch change gearing continue to operate. When the pitch change has been completed the pilot will shift the handle 2! to its neutral position. This will simultaneously disengage gear collar 84 and disengage the gears till, 42 from the pinion 31 which drives the indicator. When the pitch of the blades. is to be decreased the pilot will shift the handle M in the opposite direction to cause shaft t? to simultaneously shift the gear-collar M to bring the other Worm into engagement with the pitch change gearing carried by the hub and to simultaneous- 1y, through flexible shaft i, shift the cam-slide hi to bring the other of the gears 4t, it into en gagement with the pinion 3i so that the pitch change gearing will be driven to reverse the movement of the pointer 29 and to correspondingly indicate the degree of pitch decrease. Ii" the pilot does not shift the handle it to its men 1 tral position when the blades are shifted to their low-pitch limit, the pointer 2t willbe arrested by one of the stops at to indicate the minimum pitch of the propeller blades.

In Figs. 11 and 12 there is illustrated a modiiied 'form of the invention in which the stem of. the handle 2| to which the flexible shaft Ell is connected, is provided with a cam M which is adapted to rock an elbow lever 85, one arm of which is normally pressed against the cam by a spring 96. The other arm of the lever is seated in a socket 81 in a plunger 98 which is slidably mounted in the bracket 89 in which the stem Mi is also mounted. The plunger 89 is connected by a flexible connector 90 to a fork 911 (Fig. 12). This fork is pivoted to a bracket 92 which is pivoted to swing around the axis of a pinion 93 which is constantly driven from the flexible engine driven shaft 29. In this form of the invention the pointer 24' has the slip connection with its shaft 94 which is journalled in the indicator case. This pointer moves across a calibrated dial 95. A worm gear 96 is fixed to the pointer shaft 94 and a worm 91 is fixed to a shaft 98 which is journalled in the indicator case.

Worm 91 meshes with the worm gear 99 and a gear 99 is fixed to shaft 99. A gear I99 meshes constantly with the pinion 99 and with a gear I91. Gearsiflll, "II are mounted in the bracket 92 so that by swinging the bracket either of the gears lllll, IIH may be engaged with the gear 99 to selectively shift the pointer of the indicator in either direction according to the pitch changes. In this form of the invention cam 84 shifts the lever 85 and connector 99 to control the movements 0! the bracket 92 and operation of the indicator gearing from pinion 93.

In Figs. 12 to 14, the invention is exemplified with a pointer I04 which is adapted to move in a rectilinear path across a fixed scale I05. The hub of the pointer I is threaded to a screw I96 on a shaft 191 which is journalled in the sides of a casing I08. The hub of pointer I04 has a flattened front portion I09 which engages the front wall of the casing so that it will be held against rotation so the rotation of the screw will move the pointer longitudinally of the shaft HIT. A gear H0. is fixed to one end of the shaft lll'l. This gear is adapted to be driven by reversible gearing comprising constantly driven pinion 99 and gears 109 and ml which are mounted in bracket 92 which is pivoted to swing around the axis of pinion 93. A shifter rod 9| is adapted to swing the bracket to engage either of the gears Hill, HH and gear ill] on shaft I01.

A bar i H is slidably mounted in the casing we above the shaft I01 and carries adjustable stops H2 for limiting the movement of the pointed to the predetermined pitch limits for the pitch limits provided for in the pitch change gearing. These stops are adjustably mounted on bar 1 II by bolts H3 which extend through elongated slots in the bar. The bar Hi is normally positioned by a resilient strip SM,- which has one of its ends.

extended into a notch in the bar iii and its other end fixed to casing I09. This spring permits the bar Hi to be shifted slightly by the hub of the pointer illl when it engages one of the stops H2. Bar Ill is provided with a yoke lit which straddles the gear l ill. Pins I 19 project from the faces oi gear Mil and when the bar H l is shifted in either direction the yoke H9 will engage one of the pins lit and prevent further rotation of the gear illl. In this form of the invention the pinion it? is frictionally driven from its shaft ill) so that when gear H9 is arrested by bar ill the shaft which is continuously driven from the engine may continue to rotate without driving the screw shaft till.

I The invention exemplifies conjointly controlled pitch change gearing and gearing for the pitch indicator which is adapted to be driven from the engine. The invention also exemplifies a pitch indicator in which provision is made for arresting the pointer at the predetermined pitch limits provided for in the pitch change gearing to maintain the correct indications and to permit rectification at the pitch limits for any differential movement resulting from the coupling and unbe modified within the scope of the appended claims, without departing from the spirit and scope of the invention,

What I claim as new and desire to secure by Letters Patent is:

\ ing mechanism for changing the pitch oi propel-' 1. The combination of an element for operating mechanism for changing the pitch of propeller blades, operable by rotation of the propeller, a pitch-indicator, a connection for driving the indicator from the engine, said connection being separate from the pitch-changing mechanism, and means for conjointly controlling said element and said indicator driving connection.

2. The combination of an element for operatler blades, operable by rotation of the propeller, a pitch-indicator, a, connection ior driving the indicator in opposite directions from the engine, said connection being separate from the pitchchanging mechanism, and means for coniointly controlling said element and said indicator driving connection.

3. The combination of an element for operating mechanism for changing the pitch of propeller blades which is operable by rotation 01' the propeller, a pitch indicator, a connection for operating the indicator in opposite directions from the tachometer oi the engine, and means for coniointly controlling said element and said I power driven mechanism for changing the pitch oi propeller blades, a pitch indicator, mechanism for operating the indicator proportionately to the pitch changes, means for conjointly controlling said element and indicator operating mechanism and means for limiting the indicator for predetermined pitch changes independently of said operating mechanism.

6. The combination of means for operating power driven mechanism for changing the pitch of propeller blades in either direction, a pitch indicator; mechanism for operating the indicator in opposite directions proportionately to the pitch changes and adapted to be driven by the engine, means for conjointly controlling said mechanisms, and means for limiting the indicator to predetermined pitch changes independently of said means for operating the pitch change mechanism.

'1. The combination of means'ior operating power driven mechanism for changing the pitch or propeller blades in either direction, a pitch indicator, mechanism, separate from the pitch changing mechanism, for operating the indicator proportionately to the pitch changes and, adapted to be driven by the engine, means for conjointly controlling said operating means and said mechanism, and means for limiting the indicator to predetermined limits of pitch changes independently of the operating means.

8. The combination means for operating power driven mechanism for changingtne pitch of propeller blades, a pitch indicator, engine driven mechanism, separate from the pitch changing mechanism, for operating the indicator proportionately to the pitch changes, means for coniointly controlling said operating means and mechanism, adjustable. stops for the indicator, and a slip connection for permitting the indicator to be arrested by the stops to correspond to the predetermined limits of pitch adjustment of the blades while the indicator operating mechanism continues to run.

9. The combination 0! means for operating engine driven mechanism for changing the pitch of propeller blades in either direction, a pitch indicator, mechanism separate from the pitch changing engine driven mechanism for operating the indicator in opposite directions proportion ately to the pitch-changes, means for conjointly controlling said mechanisms, adjustable stops for' the indicator, and a slip connection for permitting the indicator to be arrested by the stops to correspond to the predetermined limits of pitch adjustment oi the blades while the indicator operating mechanism continues to run.

10. The combination oi means for operating power driven mechanism for changing the pitch of propeller blades in either direction, a pitch indicator, mechanism for operating the indicator proportionately to the pitch changes and adapted to be driven by the engine, and means for automatically synchronizing the indicator to correspond to predetermined limits of. pitch adjustment of the blades. I

11. The combination of means for operating power-driven mechanism for changing the pitch of propeller blades in either direction, a pitch indicator, mechanism for operating the indicator from the engine separately from the pitch change mechanism and in accordance with pitch-changes, comprising reduction gearing and reverse-gearing to shift the indicator for operating the reduction gearing in opposite directions, and a control device for the indicator-operating and the pitchchange mechanisms connected to control the reverse gearing.

12. The combination of means for operating power-driven mechanism for changing the pitch of propeller blades in either direction, 'a pitch indicator, mechanism for operating the indicator from the tachometer of the engine in accordance with pitch-changes and comprising reduction gearing and reverse gearing for shifting the indicator in opposite directions, and a control device for the indicator-operating and the pitch-changing mechanisms connected to control the reverse gearing.

13. The, combination of means for operating power-driven mechanism for changing the pitch of propeller blades in either direction, a pitch indicator, mechanism, separate from the pitch change mechanism, for operating the indicator from the engine, a control handle, a flexible control connection between the handle and the pitch changing mechanism, and a flexible control connection between the handle and the mechanism for operating the indicator.

14. The combination of means for operating power-driven mechanism for changing the pitch of propeller blades in either; direction, a pitch indicator, mechanism for operating the indicator in accordance with pitch changes, comprising 'reduction gearing and reverse gearing, a pivotal mount for the reverse gearing, and a control device connected to said mount and to said operating-mechanism to simultaneously control the operation of the indicator and to control said tion gearing, reverse gearing, and a screw thread for shifting the pointer, and means for simultaneously controlling the pitch-change and indicator-operating mechanisms comprising means for limiting the movements of the pointer, to correspond with predetermined pitch limits independently of the operating means.

16.-The combination of means for operating power-driven mechanism for changing the pitch of the propellers in either direction, a pitch indicator, comprising a rectilinearly movable pointer. mechanism for operating the indicator from the engine responsively to pitch changes comprising reduction gearing, reverse gearing and a screwthread for shifting the pointer, a movable bar provided with stops for arresting the pointer, and means operable by the bar for limiting the movements of the pointer, to correspond with predetermined pitch limits.

17. The combination of vmeans for operating power driven means for varying the pitch of propeller blades in either direction, a pitch indicator, mechanism for operating the indicator from the engine responsively to pitch changes, comprising gearing for operating the indicator in opposite directions, a control device connected to conjointly control the pitch change gearing in either direction and to control the operation of the indicator in opposite directions, and means for arresting the indicator at predetermined limits, independently of the control device.

18. The combination with a variable pitch propeller, its propeller shaft, shaft-operated means for changing the pitch of the propeller and a controlling means for said pitch-changing means, of a pitch indicator comprising an indicating member, a driving connection from thepropeller shaft to the indicating member independent of said pitch changing means, and means governed an by said controllingmeans for causing said driving connection to selectively drive said indicating member in opposite directions.

19. In combination, a variable pitch propeller,

. of said driving connections, and means for selectively engaging said clutches dependent upon the direction of operation of said pitch-changing means.

20. In combination, a variable pitch propeller, a propeller shaft, means for changing the pitch of the propeller, a controlling means for the pitch-changing means movable in opposite directions for respectively effecting an increase or decrease in the pitch of the propeller, and a pitch indicator comprising an indicating member, two driving connections from the propeller shaft to said indicating member, one of said driving connections tending to drive the indicating member in one direction and the other of said driving connections tending to drive theindicating memher in the opposite direction, a normally disengaged clutch included in each of said driving connections, and means governed by the direction of movement of saidcontrolling means for selectively engaging said clutches.

21. The combination with a power source, a mechanism, and a controllable operating means for operating said mechanism in reverse direc tions by means of powerderived from said power source, of an indicator, controllable operating means independent of said first operating means for operating said indicator in reverse directions by means of power derived from said power source, and a common means for simultaneously controlling both operating means.

NIITCELL W. MANCHESTER. 

